SPC AC 091726
DAY 2 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1226 PM CDT SUN MAR 09 2008
VALID 101200Z - 111200Z
...NO SVR TSTM AREAS FORECAST...
...TX...
POSITIVELY-TILTED UPPER TROUGH...CURRENTLY LOCATED OVER THE SWRN
STATES...SHOULD EXTEND FROM THE SRN PLAINS TO NRN MEXICO BY 12Z
MONDAY AS WRN MOST EMBEDDED IMPULSE/JET STREAK NOW OVER AZ DIGS SEWD
INTO NRN MEXICO DURING DAY 1. THE MAIN UPPER TROUGH IS FORECAST TO
DE-AMPLIFY SOME ON MONDAY AS IT TRACKS EWD REACHING THE OZARKS TO TX
COASTAL PLAIN BY 12Z TUESDAY. IN THE LOW LEVELS...ATTENDANT SURFACE
LOW SHOULD REMAIN OVER THE MEXICAN-SIDE OF THE LOWER RIO GRANDE
VALLEY AS IT TRACKS SEWD FROM NRN COAHUILA. INVERTED TROUGH
INITIALLY EXTENDING NEWD THROUGH DRT TO NERN TX AT 12Z MONDAY WILL
SPREAD SEWD REACHING THE TX COAST BY MONDAY EVENING /11/00Z/...
PRIOR TO MOVING INTO THE WRN GULF. A SECOND SURFACE LOW MAY FORM
ACROSS THE MIDDLE TX COASTAL PLAIN AT THE INTERSECTION OF THE SEWD
MOVING INVERTED TROUGH AND WRN EXTENT OF WARM FRONT...WITH THIS LOW
TRACKING INTO THE NWRN GULF MONDAY NIGHT.
ALTHOUGH MOISTURE RETURN WILL SUPPORT SURFACE DEWPOINTS IN THE LOWER
60S...MODEST LAPSE RATES AROUND 7 C/KM WILL TEND TO RESULT IN WEAK
SBCAPE AOB 700 J/KG. ASCENT ATTENDANT TO APPROACHING SWRN STATES
TROUGH AND WEAK LOW LEVEL WAA SHOULD MAINTAIN ANAFRONT-TYPE
CONVECTION AS THE INVERTED TROUGH SPREADS SEWD. THIS ASCENT AND
SURFACE HEATING ARE EXPECTED TO SUPPORT SURFACE-BASED TSTMS IN THE
MIDDLE AND LOWER TX COASTAL REGIONS. STRONG BAND OF SWLY MID LEVEL
WINDS EXTENDING ACROSS THE MOIST AXIS WILL CONTRIBUTE TO EFFECTIVE
BULK SHEAR FOR ORGANIZED STORMS. HOWEVER...MODEST LAPSE RATES/WEAK
INSTABILITY SHOULD LIMIT THE SEVERE WEATHER THREAT AS INDICATED BY
THE INITIAL DAY 2 OUTLOOK FOR THIS REGION PRIOR TO THE INVERTED
TROUGH MOVING OFFSHORE MONDAY NIGHT. SLY LOW LEVEL WINDS ARE
FORECAST TO WEAKEN THROUGH DAY 2 PERIOD WHICH WILL TEND TO LIMIT
CONVERGENCE AND LOW LEVEL SHEAR FOR MORE ROBUST TSTM DEVELOPMENT. A
FEW STRONGER STORMS MAY PRODUCE MARGINALLY SEVERE HAIL OR PERHAPS
WINDS APPROACHING SEVERE LEVELS. DESPITE THE WEAK LOW LEVEL
WINDS...WINDS VEERING WITH HEIGHT AND ENHANCED SHEAR IN VICINITY OF
SECONDARY LOW COULD PRODUCE AN ISOLATED TORNADO.
...SOUTH FL...
WEAK WAA REGIME ACROSS S FL IN ADVANCE OF SUB-TROPICAL IMPULSE
TRACKING EWD ACROSS THE GULF TO FL ON DAY 2 SUGGESTS POTENTIAL FOR A
FEW TSTMS ACROSS THIS REGION. POOR LAPSE RATE ENVIRONMENT AND WEAK
LOW LEVEL CONVERGENCE SHOULD LIMIT THE INLAND TSTM THREAT...WITH
GREATER POTENTIAL IN THE FL STRAITS WHERE INSTABILITY WILL BE A
LITTLE STRONGER OVER THE WARMER WATERS.
..PETERS.. 03/09/2008
CLICK TO GET WUUS02 PTSDY2 PRODUCT
NOTE: THE NEXT DAY 2 OUTLOOK IS SCHEDULED BY 0800Z
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